Prior to the present invention, there have been known E-64 (U.S. Pat. No. 3,911,111), its intermediates [Chemical Abstracts, 87, 202108y (1977), ibid., 87, 85238c (1977), ibid., 87, 202125b (1977) and ibid. 87, 68128z (1977)], and epoxysuccinic acid derivatives having acyl or amino acid moieties attached to their carbonyl groups (German Patent Application Laying Open No. P 28 09 036) prepared by several of the present inventors.
The novel epoxysuccinamic acid compounds of the present invention are distinguished from the known compounds as described above by their excellent anti-inflammatory activity.